1. Field of the Invention
The present invention relates to an image reading apparatus that reads image information from an original document, and more particularly to an image reading apparatus that receives an image reading command from a host apparatus via a network.
2. Description of the Related Art
A conventional image reading system includes an image reading apparatus connected to a network such as a local area network (LAN). The image reading apparatus reads an image form an original document, and transmits the image to a personal computer via the network. If the image data is classified, the image data should be protected from third parties. JP 2002-232630 discloses one such image reading system.
This image reading system is configured such that image data read by an image reading apparatus is stored together with a password in an image processing apparatus. If a host computer transmits a request for the image data together with the same password as that stored in the image processing apparatus, the image processing apparatus transmits the image data to the host computer.
For conventional image reading systems that employ pull-scan technology, a host computer transmits a command to read the image of an original document after the original document is placed in an image reading apparatus. The image data may be stolen by an unauthorized host computer if the a command to read the image of an original document is sent to the image reading apparatus from the unauthorized computer, after the image data has been read from the original document and before a password has been given to the image data by an authorized host computer.